Mice 

Mouse Droppings: mice leave 50-80 droppings a night, which are small and dark (approx. 3 - 8 mm in length) and scattered randomly. Look for droppings particularly along walls, in cupboards or under sinks. Not only are mouse droppings unsightly to come across, but this is one way in which mice can spread diseases.  

Grease marks (smudges or smears): these are caused by mouse fur constantly brushing against walls, floors and skirting on regular routes. You may find dark smears around holes or around corners.

Urine and urine pillars: mice urinate everywhere they go to keep track of the places they’ve been and as a way of leaving messages behind for other mice. In established or heavy infestations, body grease, combined with dirt and urine, builds up into small mounds, up to 4cm high and 1cm wide.

Scratching noises: people often report hearing unusual scratching noises at night when mice are most active. Listen for noises between partition walls, under floorboards, in false ceilings, basements and lofts.

Nests: mice use easy to shred materials, such as newspaper and fabrics, together with other soft materials to line their nest. Check lofts, suspended ceilings, cavity walls, under floorboards and behind fridges, under stoves and in airing cupboards. Nests will often contain young mice.

Tracks (footprints): rodent tracks and tail marks can show up in dusty environments such as unused lofts and basements. To check for activity, sprinkle flour, talcum powder or china clay and check for fresh tracks the next day.

Live or dead mice: spotting a mouse during the daytime can be an indication of a heavy mouse infestation.

Strong smell: mice urinate frequently and their urine has a strong ammonia-like smell. The smell may be very strong near the main site of activity or in enclosed spaces. This smell can linger for a long time (even after an mouse infestation has been removed).